A multi-institutional survey of interventional radiology for type II endoleaks after endovascular aortic repair: questionnaire results from the Japanese Society of Endoluminal Metallic Stents and Grafts in Japan

Abdominal Aortic Aneurysm Shrinkage up to 2 Years Following Endovascular Repair with PEmbolization for Preventing Type 2 Endoleak: A Retrospective Single Center Study

BACKGROUND

The aim of the present study was to evaluate the efficacy of preemptive embolization of aneurysm side branches that cause type 2 endoleak (T2EL).

METHODS

We performed a retrospective review of consecutive patients who underwent endovascular aneurysm repair (EVAR) in our facility between April 2009 and April 2019. All the patients underwent the preemptive embolization for preventing T2EL since April 2014. The patients were divided into the nonembolization group (between April 2009 and May 2014) or the embolization group (between April 2014 and April 2019). We used a support wire to improve a success rate of the preemptive embolization. The aneurysm sac shrinkage (≧5 mm), freedom from all-cause death and aneurysm-related death, T2EL-related reinterventions, aneurysm sac enlargement (≧5 mm), and complications related to the endovascular procedure were compared between the 2 groups.

RESULTS

Two-hundred patients with abdominal aortic aneurysm were included. They were divided into the nonembolization group (N = 103) and the embolization group (N = 97). We successfully embolized 89% of all the patent aneurysm side branches in the embolization group. The characteristics of the 2 groups were similar except for hypertension, patent lumbar arteries, and the use of Zenith, Excluder, and Endurant. The preemptive embolization group showed better aneurysm sac shrinkage (73% vs. 42%; P < 0.0001), no aneurysm sac enlargement (0% vs. 5%; P < 0.05), and lower T2EL-related reintervention rate (hazard ratio, 0.11; 95% confidence interval, 0.0061-0.60; P < 0.01) up to 2 years after EVAR. There were no significant differences in freedom from all-cause death, aneurysm-related death, and complications between the 2 groups.

CONCLUSIONS

The present study showed the high success rate of preemptive embolization of aneurysm side branches resulting in better anatomical changes in the aneurysm sac and lower T2EL-related intervention rate in the embolization group up to 2 years after EVAR.

Outcomes of embolization procedures for type II endoleaks following endovascular abdominal aortic repair

OBJECTIVE

The objective of this study was to investigate the mid-term outcomes of embolization procedures for type II endoleak after endovascular abdominal aortic repair, and clarify the risk factors for aneurysm enlargement after embolization procedures.

METHODS

This was a retrospective multicenter registry study enrolling patients who underwent embolization procedures for type II endoleaks after EVAR from January 2012 to December 2018 at 19 Japanese centers. The primary end point was the rate of freedom from aneurysm enlargement, more than 5 mm in the aortic maximum diameter, after an embolization procedure. Demographic, procedural, follow-up, and laboratory data were collected. Continuous variables were summarized descriptively, and Kaplan-Meier analyses and a Cox regression model were used for statistical analyses.

RESULTS

A total of 315 patients (248 men and 67 women) were enrolled. The average duration from the initial embolization procedure to the last follow-up was 31.6 ± 24.6 months. The rates of freedom from aneurysm enlargement at 3 and 5 years were 55.4 ± 3.8% and 37.0 ± 5.2%, respectively. A multivariate analysis revealed that a larger aortic diameter at the initial embolization procedure and the presence of a Moyamoya endoleak, defined as heterogeneous contrast opacity with an indistinct faint border, were associated with aneurysm enlargement after embolization management.

CONCLUSIONS

The embolization procedures were generally ineffective in preventing further expansion of abdominal aortic aneurysms in patients with type II endoleaks after EVAR, especially in patients with a large abdominal aortic aneurysm and/or a presence of a Moyamoya endoleak.

Successful Sac Embolization to Eliminate a Type 2 Endoleak After Thoracic Endovascular Aortic Repair by Penetration of a Vascular Plug Implanted in a Left Subclavian Artery

PURPOSE

To describe a technique of vascular plug penetration by a guidewire with a heavy tip load for additional embolization of a type 2 endoleak after endovascular aortic aneurysm repair (EVAR).

TECHNIQUE

The technique of vascular plug penetration is effective for additional embolization of a type 2 endoleak, when large arteries such as left subclavian artery (LSA) or hypogastric artery remain patent even after the embolization of the vessel has been performed using a vascular plug and are responsible for the endoleak. A tapered guidewire with a heavy tip load enables the penetration of the disk of the plug, followed by introduction of a microcatheter into the endoleak nidus. In the presented case, the technique successfully eliminated a type 2 endoleak in a thoracic aortic aneurysm for which a patent LSA despite the embolization by a vascular plug was responsible.

CONCLUSION

The technique of vascular plug penetration allows an access to an endoleak cavity via a vascular plug placed in an aortic side branch for additional embolization of a type 2 endoleak after EVAR.

Mid-term Outcomes and Predictors of Transarterial Embolization for Type II Endoleak After Endovascular Abdominal Aortic Aneurysm Repair

PURPOSE

To evaluate the mid-term outcomes of transarterial embolization (TAE) for type II endoleak after endovascular abdominal aortic aneurysm repair (EVAR) and investigate the predictors of sac enlargement after embolization.

MATERIALS AND METHODS

We conducted a retrospective analysis of 55 patients [48 men and 7 women, median age 79.0 (interquartile ranges 74-82) years] who underwent TAE for type II endoleak from 2010 to 2018. The aneurysmal sac enlargement, endoleaks, aneurysm-related adverse event rate, and reintervention rate were evaluated. Patients' characteristics and clinical factors were evaluated for their association with sac enlargement.

RESULTS

Fifty-five patients underwent TAE with technical success and were subsequently followed for a median of 636 (interquartile ranges 446-1292) days. The freedom from sac enlargement rates at 1, 3, and 5 years was 73.2%, 32.0%, and 26.7%, respectively. After initial TAE, the recurrent type II, delayed type I, and occult type III endoleak were identified in 39 (71%), 5 (9%), and 3 (5%) patients, respectively. Although a patient had aorto-duodenal fistula, there was no aneurysm-related death. The freedom from reintervention rates was 84.6%, 35.7%, and 17.0%, respectively. In the multivariate analysis, sac diameter > 55 mm at initial TAE (hazard ratios, 3.23; 95% confidence intervals, 1.22-8.58; P < 0.05) was a significant predictor of sac enlargement.

CONCLUSION

TAE for type II endoleak was not effective in preventing sac enlargement, and reinterventions were required among the mid-term follow-up. The sac diameter > 55 mm at initial TAE was a significant predictor of sac enlargement.

Multicentre randomised controlled trial to evaluate the efficacy of pre-emptive inferior mesenteric artery embolisation during endovascular aortic aneurysm repair on aneurysm sac change: protocol of Clarify IMA study

INTRODUCTION

Type II endoleak (EL) is frequently seen after endovascular aneurysm repair (EVAR) for abdominal aortic aneurysm (AAA) and is often considered responsible for aneurysm sac enlargement if it persists. In order to reduce type II EL and consequent sac enlargement, pre-emptive embolisation of the inferior mesenteric artery (IMA), which is a main source for persistent type II EL, has been introduced in many vascular centres. At present, there is a lack of robust evidence to support the efficacy of pre-emptive embolisation of IMA on reduction of persistent type II EL with subsequent sac shrinkage.

METHOD AND ANALYSIS

This multicentre, randomised controlled trial will recruit 200 patients who have fusiform AAA ≥50 mm/rapidly enlarging fusiform AAA, with patent IMA, and randomly allocate them either to a pre-emptive IMA embolisation group or non-embolisation control group in a ratio of 1:1. The primary endpoint is the difference of aneurysm sac volume change assessed by CT scans between the pre-emptive IMA embolisation group and the control group at 12 months after EVAR. The secondary endpoints are defined as change of aneurysm sac volume in both groups at 6 and 24 months, freedom from sac enlargement at 12 and 24 months after EVAR, prevalence of type II EL at 1, 6, 12 and 24 months evaluated by contrast-enhanced CT, reintervention rate, aneurysm related mortality, overall survival, perioperative morbidity, volume of contrast media used during EVAR and dosage of radiation.

ETHICS AND DISSEMINATION

The protocol has been reviewed and approved by the ethics committee of Nara Medical University (No. 2113). The findings of this study will be communicated to healthcare professionals, participants and the public through peer-reviewed publications, scientific conferences and the University Hospital Medical Information Network Clinical Trials Registry home page.

TRIAL REGISTRATION NUMBER

UMIN000035502.

A Novel Technique for the Treatment of Type 2 Endoleak After Endovascular Aortic Repair: Sac Embolization with Balloon Occlusion of the Aorta (SEBOA)

PURPOSE

We presented a new method of sac embolization using n-butyl-cyanoacrylate (NBCA) with balloon occlusion of the aorta (SEBOA) that can facilitate decreasing flow rate of the involved branches with the goal of type 2 endoleak resolution after endovascular aortic repair (EVAR).

TECHNIQUE

This technique is demonstrated in six patients who required type 2 endoleak treatment including previous technical failure. A transarterial approach was performed in four patients and transabdominal direct puncture in two. Technical success was defined as complete embolization of both involved branches and sac on postoperative CT. Sacography under balloon occlusion of the aorta demonstrated decreased flow rate of the all involved branches in all patients. SEBOA was performed using 25 or 33% of NBCA diluted with lipiodol. Technical success was obtained in 3 of 6 patients, and one major complication was observed with adhesion of NBCA to the microcatheter resulting in foreign body retention.

CONCLUSION

SEBOA may help solve the difficulty of type 2 endoleak treatment after EVAR as decreased flow rate of the involved branches under balloon occlusion of the aorta was achieved in all patients. However, protocols regarding concentration of NBCA or using other embolic materials are needed to improve the success rate.

The Influence of 4 or more Patent Lumbar Arteries on Persistent Type II Endoleak and Sac Expansion after Endovascular Aneurysm Repair

BACKGROUND

This study aimed to review our clinical results and determine how preoperative patent lumbar arteries (LAs) influence the occurrence of type II endoleaks or aneurysm sac enlargement after endovascular aneurysm repair (EVAR) and to identify the preoperative computed tomography findings of persistent type II endoleaks from patent LAs that indicate the need for preventive procedures during EVAR.

METHODS

A total of 293 patients who underwent EVAR for infrarenal abdominal aortic aneurysm (AAA) between August 2007 and July 2013 were reviewed. Follow-up data were available for 194 patients (76% male, mean age 78 ± 6.8 years), and the mean follow-up time was 57 ± 23 months.

RESULTS

The number of patent LAs was identified as a significant positive predictor of persistent type II endoleaks (hazard ratio [HR], 1.4; 95% confidence interval [CI]: 1.2-1.7; P < 0.001) and sac enlargement (≥5 mm) at the 2-year follow-up period (HR, 1.3; 95% CI: 1.1-1.8; P = 0.009) after EVAR, using Cox regression analysis. The receiver operating characteristics curve (AUC: 0.72) showed that a cutoff of 4 patent LAs resulted in a sensitivity of 87% and specificity of 48%. The rates of freedom from sac enlargement (≥5 mm) at 3 and 5 years after EVAR were significantly lower in patients with 4 or more patent LAs than in those with fewer (90% and 76% vs. 96% and 89%; P = 0.0008).

CONCLUSIONS

The number of patent LAs is associated as a significant risk factor with the development of persistent type II endoleaks and sac enlargement after EVAR. Four or more patent LAs should be recognized as the group having an elevated risk of developing late sac enlargement after EVAR.